TODO
----

0.13.x: Undo?
-------------
- Undo?

1.0.0: documentation/localization
---------------------------------
- Create a DTD for the file format
- Better documentation and/or online help
- Localization support?

1.1.x
-----
- Configurable keyboard
- Arpeggiator

1.2.x
-----
- Editing/playing multiple songs at the same time is not implemented
- Instrument specific note data maps are not implemented
